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Impacts of Climate Variability on Sustainable Agriculture in Imo State,Nigeria

Journal of Geographical Research 2021年第1期4卷 9-17页

作者： Ajiere S Diagi B.E Edokpa D.o Department of Geography and Environmental Management University of Port HarcourtPort HarcourtNigeria Departments of Environmental Management Federal University of TechnologyOwerriNigeria Departments of Geography and Environmental Management Rivers State UniversityPort HarcourtNigeria

Rainfall and Temperature are important factors in agriculture especially in Nigeria where rain-fed agriculture is practiced extensively and agriculture contributes to food security and provides employment for urban and rural ***,climate variability represents a major danger to agriculture by modifying the rainfall and temperature pattern,thereby resulting to a big peril in the sustainability of *** is the reason all countries of the world are concerned about the effects of climate variability on *** work therefore,examined the impact of climate variability on rainfall and temperature in Imo State,South Eastern *** rainfall and temperature data were gotten from Nigerian Meteorological Agency(NIMET)for a period of 30 years which was analyzed by using descriptive statistics,decadal distribution,trend graph anomalies and 5 year moving *** analysis showed increasing trend pattern in yearly maximum,minimum temperature and decrease in annual rainfall,The third order polynomial trend shows a decrease in the anomaly of annual mean rainfall(y=-0.0002x4)and a persistent increase in the mean temperature anomaly especially in the second decade(1996-2007).The discoveries show that there is a notable variability in temperature and rainfall pattern which revealed an increase in temperature and decrease in annual *** calls for serious attention as people in this part of Nigeria critically depend on rainfall for agricultural *** is recommended that government should support the agricultural sector by providing mechanized farming systems such as irrigation and drilling of water borehole in farm sites for agriculture,especially for the rural farmers and create awareness to the farmers on recent trends in climate issues to achieve sustainable agriculture.

关键词： Rainfall Temperature Climate variability Sustainable agriculture Imo State

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Assessment of Conflicts between Forestry and Agricultural Land Uses in Nigeria and Ghana

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Journal of Agricultural Science and Technology 2011年第4期5卷 462-471页

作者： B. o. Agbeja M. A. A. Derkyi Department of Forest Resources Management Faculty of Agriculture and Forestry University of lbadan Ibadan 200001 Nigeria Conservation and Development Foundation （CoNDEF）-A Non-Governmental organisation P.O. Box Ks 9668 Kumasi Ghana

The study was conducted in four states of the Southwest geo-political zone in Nigeria and four regions in Ghana.. The results showed that the existing forest, agricultural and land use decree/policies in Nigeria and Ghana indicated lack of integration between Forestry and Agricultural land uses. The main conflicting areas were obsolete land use decree in Nigeria and lack of national land use policy in Ghana. The causes and effects of the conflicts had policy enunciation, stakeholders, and institutional and managerial dimensions. Some of the causes of the conflicts were lack of national land use policies for coherent and integrated forest and agricultural sectors; high population growth, de-reservation of forest reserves, unsustainable agricultural practices and technologies, land hunger, encroachment of forest reserves with cash crops and stakeholders＇ litany of demands and other diverse interests. Consequences of conflicts in the study locations included disharmony between forestry officials and farmers, antagonism between timber concenssionnaires and communities, wanton destruction of economic trees and seedlings, extinction of tree species, expansion of illegal farm lands and an attendant poverty. The logistic regression model for conflicts between forestry and agricultural land uses in Nigeria and Ghana indicated significant fit to the data judging from chi square value （df, 9） = 3174.1 that is significant at P 〈 0.05. The final loss of the model indicated a value of 92.47.

关键词： Conflicts landuse forestry agriculture policy land hunger.

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Using meshes to change the characteristics of simulated rainfall produced by spray nozzles

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International Soil and Water Conservation Research 2014年第2期2卷 67-78页

作者： Sílvia C.P.Carvalho João L.M.P.de Lima M.Isabel P.de Lima Department of Civil Engineering Faculty of Science and TechnologyUniversity of CoimbraCoimbraPortugal Department of Civil Engineering Campus II-University of CoimbraRua Luís Reis Santos3030-788 CoimbraPortugal

Rainfall simulators have been used for many years contributing to the understanding of soil and water conservation ***,rainfall simulators’design and operation might be rather demanding for achieving specific rainfall intensity distributions and drop characteristics and are still open for *** study explores the potential of combining spray nozzle simulators with meshes to change rainfall characteristics,namely drop properties(drop diameters and fall speeds).A rainfall simulator laboratory set-up was prepared that enabled the incorporation of different wire meshes beneath the spray *** tests conducted in this exploratory work included different types of spray nozzles,mesh materials(plastic and steel),square apertures and wire thicknesses,and positions of the meshes in relation to the *** intensity and drop size distribution and fall speed were *** showed that the meshes combined with nozzles increased the mean rainfall intensity on the 1 m^(2) control plot below the nozzle and altered the rain drops’properties,by increasing the mass-weighted mean drop diameter,for example.

关键词： Rainfall simulators Spray nozzle meshes Drop characteristics

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扬布拉德一家

扬布拉德一家

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作者： J.o.·基伦斯(J.o. Killens)

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Investigation of the Potential of Near Infrared Spectroscopy for the Detection and Quantification of Pesticides in Aqueous Solution

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American Journal of Analytical Chemistry 2011年第8期2卷 53-62页

作者： Aoife A. Gowen Yutaro Tsuchisaka Colm o’Donnell Roumiana Tsenkova 不详

This research investigates the potential of near infrared spectroscopy (NIRS) for the detection and quantification of pesticides in aqueous solution. Standard solutions of Alachlor and Atrazine (ranging in concentration from 1.25 - 100 ppm) were prepared by dilution in a Methanol/water solvent (1:1 methanol/water (v/v)). Near infrared transmission spectra were obtained in the wavelength region 400 - 2500 nm;however, the wavelength regions below 1300 nm and above 1900 nm were omitted in subsequent analysis due to the poor signal repeatability in these regions. Partial least squares analysis was applied for discrimination between pesticide and solvent and for prediction of pesticide concentration. Limits of detection of 12.6 ppm for Alachlor and 46.4 ppm for Atrazine were obtained.

关键词： Pesticide Aquaphotomics Nearinfrared

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Social opinion Network Analytics in Community Based Customer Churn Prediction

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Journal on Big Data 2022年第2期4卷 87-95页

作者： Ayodeji o.J Ibitoye olufade F.W onifade Country bowen University Iwo+234Nigeria University of Ibadan Ibadan+234Nigeria

Community based churn prediction,or the assignment of recognising the influence of a customer’s community in churn prediction has become an important concern for firms in many different *** churn prediction until recent times have focused only on transactional dataset(targeted approach),the untargeted approach through product advisement,digital marketing and expressions in customer’s opinion on the social media like Twitter,have not been fully *** this data source has become an important influencing factor with lasting impact on churn *** Social Network Analysis(SNA)has become a blended approach for churn prediction and management in modern era,customers residing online predominantly and collectively decide and determines the momentum of churn prediction,retention and decision *** existing SNA approaches,customers are classified as churner or non-churner(1 or 0).oftentimes,the customer’s opinion is also neglected and the network structure of community members are not ***,the pattern and influential abilities of customers’opinion on relative members of the community are not ***,the research developed a Churn Service Information Graph(CSIG)to define a quadruple churn category(churner,potential churner,inertia customer,premium customer)for non-opinionated customers via the power of relative affinity around opinionated customers on a direct node to node *** essence is to use data mining technique to investigate the patterns of opinion between people in a network or ***,every member of the online social network community is dynamically classified into a churn category for an improved targeted customer acquisition,retention and/or decision supports in churn management.

关键词： Churn prediction social network analysis community detection opinion mining

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Numerical Techniques Used in Modeling Codes for Dual-Reflector Antenna Design and Analysis

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Journal of Systems Engineering and Electronics 1993年第2期4卷 63-74页

作者： Wang Welling, Wang Shijin and Chen JingxiongBeijing Institute of Radio Measurement, P. o. Box 3923, Beijing 100854, China Beijing Institute of Radio Measurement P. O. Box 3923 Beijing 100854 China

An user-oriented computer software consisting of three modeling codes, named DRAD, DRAA and FDPAT, is introduced. It can be used to design three types of Cassegrain system: classical, with shaped subreflector and with dual shaped reflectors, and to analyse radiation patterns for the antennas. Several mathematical models and numerical techniques are presented.

关键词： Software Numerical technique Antenna Dual-reflector antenna Cassegrain system.

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Policy implications for awareness gaps in antimicrobial resistance(AMR)and antimicrobial use among commercial Nepalese poultry producers

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Global Health Research and Policy 2021年第1期6卷 447-455页

作者： Anastasia S.Lambrou Gabriel K.Innes Laura o’Sullivan Himal Luitel Rebanta K.Bhattarai Hom *** Christopher D.Heaney Department of International Health Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA Department of Epidemiology Rutgers School of Public HealthPiscatawayNJUSA Department of Environmental Health&Engineering Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA Center for Biotechnology Agriculture and Forestry UniversityRampurChitwanNepal Department of Veterinary Microbiology and Parasitology Agriculture and Forestry UniversityRampurChitwanNepal Department of Epidemiology Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA

Background:Nepal’s poultry industry has increased with a growing middle class,which has translated to an increase in antimicrobial consumption and thus a rise in antimicrobial resistance(AMR).Describing and understanding antimicrobial use practices among commercial poultry producers in Nepal may help minimize the risks of AMR development in both humans and animals and determine the effectiveness of relevant ***:From July to August 2018,poultry farmers were randomly recruited from Nepal’s Chitwan District to participate in a cross-sectional *** lead producer in each poultry operation was administered a quantitative structured-survey via a 30-min *** were asked to provide demographics,production practices,and knowledge about their antimicrobial use *** data analysis was performed to obtain frequencies and compare ***:In total,150 commercial poultry producers of whom raised between 300 and 40,000 birds completed the *** 33%(n=49)of producers reported knowing what AMR was,and among them only 50%(n=25)consulted a veterinarian for treatment *** administration for growth promotion was still employed by 13%of poultry ***,critically important antimicrobial drugs,specifically colistin,were identified at 35%of participating *** reported low overall understanding and compliance of withdrawal periods(n=41;27%),which may result in both AMR development and adverse health reactions among consumers who ingest antimicrobial *** Nepal has publicized antimicrobial use policies and awareness campaigns to instill healthy production practices,most producers(82%)were unaware of ***:Many Nepalese poultry producers lack overall antimicrobial use and AMR awareness,which is evidenced by low antimicrobial withdrawal period compliance,use of antimicrobials for growth promotion,and the sustained use of critically important ***

关键词： Antimicrobial resistance Withdrawal period Poultry Nepal one health Health policy

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A Mathematical Modelling of the Effect of Treatment in the Control of Malaria in a Population with Infected Immigrants

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Applied Mathematics 2018年第11期9卷 1238-1257页

作者： olaniyi S. Maliki Ngwu Romanus Bruno o. onyemegbulem Department of Mathematics Michael Okpara University of Agriculture Umudike Nigeria African Center of Excellence in Phytomedicine Research and Development University of Jos Jos Nigeria

In this work, we developed a compartmental bio-mathematical model to study the effect of treatment in the control of malaria in a population with infected immigrants. In particular, the vector-host population model consists of eleven variables, for which graphical profiles were provided to depict their individual variations with time. This was possible with the help of MathCAD software which implements the Runge-Kutta numerical algorithm to solve numerically the eleven differential equations representing the vector-host malaria population model. We computed the basic reproduction ratio R0 following the next generation matrix. This procedure converts a system of ordinary differential equations of a model of infectious disease dynamics to an operator that translates from one generation of infectious individuals to the next. We obtained R0 = , i.e., the square root of the product of the basic reproduction ratios for the mosquito and human populations respectively. R0m explains the number of humans that one mosquito can infect through contact during the life time it survives as infectious. R0h on the other hand describes the number of mosquitoes that are infected through contacts with the infectious human during infectious period. Sensitivity analysis was performed for the parameters of the model to help us know which parameters in particular have high impact on the disease transmission, in other words on the basic reproduction ratio R0.

关键词： Malaria Control Infected Immigrants Basic Reproduction Ratio Differential Equations MathCAD Simulation

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CH3F与C12o2和C13o2之间的振动能转移

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中国激光 1986年第9期 588-588页

作者：蔡继业,汪晨熙,Jim o.neill,Geore Flynn 中国科学院安徽光机所中国科学院安徽光机所哥伦比亚大学哥伦比亚大学

我们采用Q开关的Co2激光9.6μm P（20）支泵浦CH3F分子的ν3振动模,以此作为能源来激发C12o2和C13o2分子的弯曲振动模ν2,研究其在非弹性碰撞过程中分子能量转移过程。我们用一种比红外荧光法（LIF）分辨率高一万倍的新方法——二极管... 详细信息

我们采用Q开关的Co2激光9.6μm P（20）支泵浦CH3F分子的ν3振动模,以此作为能源来激发C12o2和C13o2分子的弯曲振动模ν2,研究其在非弹性碰撞过程中分子能量转移过程。我们用一种比红外荧光法（LIF）分辨率高一万倍的新方法——二极管激光探测法来得到

关键词：分子 CH3F o2

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